fix: decouple IDB writes from network-data return path

QuotaExceededError from a full IndexedDB was being caught by the IIFE's
try/catch (after the earlier await-upsert change), causing repos to return
null/empty even when the network fetch succeeded. Fire-and-forget upserts
with .catch(()=>{}) ensure write failures never suppress fetched data.

client/src/repo/todoRepo.ts

@@ -13,7 +13,7 @@ export const todoRepo = {
     const refresh = (async () => {
       try {
         const result = await todoApi.list(tripId)
-        await upsertTodoItems(result.items)
+        upsertTodoItems(result.items).catch(() => {})
         return result
       } catch {
         return null